In Tennis, 23-time Grand Slam champion Serena Williams has withdrawn from the ongoing Italian Open due to a knee injury.

The 37-year old was all set to clash with her sister Venus in the second round of the tournament in Rome today. Serena is a four-time Italian Open champion and holds the record for the most number of wins by a player in the tournament.

With Serena's withdrawal, Venus has progressed to the third round. Venus will now play fellow American Sloane Stephens. Italian Open is the last big event before the French Open which begins in Paris later this month.